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chinese Journal of Polymer Science 2015年第2期33卷 236-244页

作者： P.Priyanka A.B.Arun c.c.Young P.D.rekha Yenepoya Research centre Yenepoya University Department of Soil and Environment Sciences National Chung-Hsing University

In this study, bacteria associated with marine organisms were screened for the production of exopolysaccharides（EPSs） on MY media containing sea salts（2.5%-10%）. Three selected isolates were identified as Alteromonas sp. PRIM-21, Nitratireductor sp. PRIM-24 and Enterobacter sp. PRIM-26 using 16 S r RNA gene sequencing. Optimization of the growth and EPS production kinetics in relation to incubation time were assessed. The purified EPS yield was 590, 650 and 540 mg·L-1 culture media respectively in Alteromonas sp. PRIM-21, Nitratireductor sp. PRIM-24 and Enterobacter sp. PRIM-26. Biochemical and FTIR analyses revealed the presence of biologically important functional groups in the EPS produced by all the three isolates. The EPS produced by Nitratireductor sp. PRIM-24 and Alteromonas sp. PRIM-21 showed 2.0% sulfate content. These bacterial EPS also showed antioxidant and emulsifying activities and the EPS produced by Enterobacter ***-26 showed significantly higher antioxidant activities in terms of superoxide（Ic50 0.33 mg·mL -1） and DPPH（Ic50 0.44 mg·mL -1） radical scavenging. It also showed higher emulsifying activities against selected hydrophobic substrates with EI24 values above 60%. From the results of the study, it can be concluded that the isolated bacteria produce EPS that can be investigated in detail for biotechnological applications.

关键词： Marine bacterial exopolysaccharides Alteromonas Nitratireductor Enterobacter Antioxidant activity Emulsification

A review of paediatric vision screening protocols and guidelines

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International Journal of Ophthalmology(English edition) 2019年第7期12卷 1194-1201页

作者： Uchenna c.Atowa Samuel O.Wajuihian rekha Hansraj Discipline of Optometry University of KwaZulu-Natal

Vision screening plays an important role in the early detection of children who have or probably are predisposed to have specific visual problems. The validity and reliability of the screening batteries in relation to the age group to be screened, and the person administering the test as well as the referral and follow-up criteria contribute to the overall outcome of the vision screening. Despite the long history of vision screening and significant improvement in the development of screening protocols, no agreement exists concerning the age at which children should be screened, the exact test batteries that should be included and who should conduct the screening. This review highlights some important aspects of the history of paediatric vision screening and available evidence in support of their use to detect visual conditions in children. It also examines some of the barriers against the development of paediatric vision screening models especially in low and medium income countries.

关键词： vision screening children visual problems screening batteries

Visual problems: a review of prevalence studies on visual impairment in school-age children

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International Journal of Ophthalmology(English edition) 2019年第6期12卷 1037-1043页

作者： Uchenna c.Atowa rekha Hansraj Samuel O.Wajuihian Discipline of Optometry University of KwaZulu-Natal

childhood visual impairment(VI) have a significant impact on the educational achievement, career choices and social life of affected individual, and in children, is mainly due to either preventable or treatable causes. Reliable data on the prevalence and causes of VI in children will guide the development of a systematic vision screening program for its early detection and successful treatment of possible causes. The purpose of this literature review is to summarize the available data on prevalence and causes of VI in school-age children from various regions globally. A discussion on the major findings highlighting the definition criteria, classifications and limitations for further studies is also presented.

关键词： visual impairment school-age children vision screening school performance

Growth response of three plantation species of the tropics exposed to elevated cO_2 levels

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Journal of Forestry Research 2013年第3期24卷 449-456页

作者： rekha R. Warrier c. Buvaneswaran P. Priyadharshini R.S.c. Jayaraj Institute of Forest Genetics and Tree Breeding Forest CampusR. S. Puram Coimbatore 641002 India

The response of forest trees, the largest carbon sinks on the earth, to continuing rise in atmospheric carbon levels is unknown. Re- ports state that increasing levels of atmospheric cO2 will stimulate pho- tosynthesis and productivity in most ecosystems. However, the duration and magnitude of this stimulation, particularly in the tropics, remains a question. To investigate the effects of cO2 fertilization on plant growth, seedlings of three common plantation species, casuarina equisetifolia, Ailanthus excelsa and Tectona grandis were grown in closed chambers enriched with cO2. After 180 days of treatment, morphological traits of seedling height, biomass of root and shoot and root-shoot allometric co-efficient were measured. The activity of carbonic anhydrase and con- tents of chlorophylls, total carbohydrates and soluble proteins were de- termined. In Tectona grandis, significant effects of cO2 supply were found on chlorophylls, root-shoot allometric ratio and seedling quality index. Ailanthus excelsa showed significant effect on only the shoot characteristics on exposure to elevated cO2 but the root characteristics and concentrations of chlorophylls were not significantly different. ca- suarina equisetifolia also showed significant effects on exposure to ele- vated cO2 in terms of shoot characteristics and concentrations of chlo- rophylls. Total sugars, the major photosynthates, did not show any sig- nificant variation to elevated cO2 in any of the three species. carbonic anhydrase, the key enzyme responsible for transfer of cO2 into the tis- sues significantly increased in all three species. Overall, all the variables responded to elevated cO2, reflecting the positive effects of one parame- ter of climate change conditions on seedling quality. A positive response of these three plantation species to elevated cO2 content is a good indi- cation for their future existence in potentially changed climatic eonditions.

关键词： Plantation Elevated cO2 Tropical trees India carbonicanhydrase

An Enhanced Security System Using Blockchain Technology for Strong FMc Relationship

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Intelligent Automation & Soft computing 2023年第1期35卷 111-128页

作者： K.Meenakshi K.Sashi rekha Department of computer Science and Engineering Saveetha School of EngineeringSaveetha Institute of Medical and Technical SciencesChennaiIndia

Blockchain technology is a shared database of logs of all consumer transactions which are registered on all machines on a *** transactions in the system are carried out by consensus processes and to preserve confidentiality all thefiles contained cannot be *** technology is the fundamental software behind digital currencies like Bitcoin,which is common in the *** computing is a method of using a network of external machines to store,monitor,and process information,rather than using the local computer or a local personal *** software is currently facing multiple problems including lack of data protection,data instability,and *** paper aims to give the highest security for multiple user environments in cloud for storing and accessing the data in *** users who are legitimate are only allowed for storing and accessing the data as like a secured block chain *** like the Blockchain which does not require a centralized system for transactions,the proposed system is also independent on centralized network *** decentralized system is developed in such a way to avoid *** system enables the fabricator to spend less or null resources to perform the validations for its direct operated *** ensures the product fabricator to avoid the circulation of its duplicate *** customer as an end-user is also ensured to have only the genuine products from the *** Fabricator(F),Merchant(M)and consumer(c)forms an interconnected triangular structure without allowing any counterfeiting agents in their secured cloud *** pro-posed approach provides the stability in the security system of the cloud using the chaining mechanism within different blocks at each *** takes roughly 4.7,6.2,and 7.5 ms,respectively,to register each node in the proposed system for 5,10,and 15 *** overall registration time for each scenario is 11.9,26.2,and 53.1 ms,despite the fact th

关键词： Blockchain bitcoin customer merchant data protection digital currencies transaction

Genetic linkage mapping and QTL identification for salinity tolerance in Indian mustard(Brassica juncea *** and coss.)using SSR markers

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Oil crop Science-中国油料作物学报英文版 2023年第3期8卷 191-205页

作者： rekha Patel Sumit Jangra Ram Avtar Neelam R.Yadav Ram c.Yadav Department of Molecular Biology Biotechnology&BioinformaticsCCS Haryana Agricultural UniversityHisar-125004India Department of Genetics and Plant Breeding CCS Haryana Agricultural UniversityHisar125004India

Soil salinity is one of the major environmental constraints that limits crop yield and nearly 7%of the total area worldwide is affected by ***-induced oxidative stress causes membrane damage during germination and seedling *** mustard is a major oilseed crop in India and its production and productivity are severely affected by salt *** Brassica cultivars for salinity tolerance by conventional means is very difficult and ***,understanding the molecular components associated with salt tolerance is needed to facilitate breeding for salt tolerance in *** this investigation,quantitative trait loci(QTLs)associated with salt tolerance were identified using F_(2:3)mapping population developed from a cross between cS52(salinity tolerant)and RH30(salinity sensitive).Parents and F_(2:3)were evaluated under controlled and salinity stress conditions for 14 morpho-physiological traits for two consecutive generations(F2 and F_(2:3)),explaining proportion of the phenotypic variance under control *** sequence repeat(SSR)markers were used for mapping studies.A genetic linkage map based on 42 simple sequence repeats(SSRs)markers was constructed covering 2298.5 cM(Haldane)to identify the loci associated with salt tolerance in Brassica ***-one SSRs showing polymorphism in the parents(cS52 and RH30)were mapped on 8 linkage groups(c1–c8).One marker(nga 129)did not map to any of the linkage group and was excluded from *** group 5(c5;317.9 cM)was longest and linkage group 1(c1,255.0 cM)was ***,we identified 15 QTLs controlling 8 traits using F_(2:3)*** QTLs explained 12.44–60.63%of the phenotypic variation with a LOD score range of 3.62–*** of these QTLs,QMI4.1 related to membrane injury showed 51.28%phenotypic variance with a LOD score of *** QBYP8.1 related to biological yield per plant showed 60.63%phenotypic variance at a LOD score of *** highest LO

关键词： Brassica juncea Salt stress tolerance SSR markers Linkage mapping QTL identification

A Single-Tube, Functional Marker-Based Multiplex PcR Assay for Simultaneous Detection of Major Bacterial Blight Resistance Genes Xa21, xa13 and xa5 in Rice

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Rice science 2016年第3期23卷 144-151页

作者： S.K. Hajira R.M. Sundaram G.S.Laha A.Yugander S.M.balachandran B.c.Viraktamath K.Sujatha c.H.Balachiranjeevi K.Pranath M.Amla S.Bhaskar V.Abhilash H.K.Mahadevaswamy M.Kousik T.DilipKumar G.Harika G.rekha IcAR-Indian Institute of Rice Research Rajendranagar Hyderabad 500030 India

In marker-assisted breeding for bacterial blight(BB) resistance in rice, three major resistance genes, viz., Xa21, xa13 and xa5, are routinely deployed either singly or in combinations. As efficient and functional markers are yet to be developed for xa13 and xa5, we have developed simple PcR-based functional markers for both the genes. For xa13, we designed a functional PcR-based marker, xa13-prom targeting the In Del polymorphism in the promoter of candidate gene Os8N3 located on chromosome 8 of rice. With respect to xa5, a multiplex-PcR based functional marker system, named xa5 FM, consisting of two sets of primer pairs targeting the 2-bp functional nucleotide polymorphism in the exon II of the gene TFIIA5(candidate for xa5), has been developed. Both xa13-prom and xa5 FM can differentiate the resistant and susceptible alleles for xa13 and xa5, respectively, in a co-dominant fashion. Using these two functional markers along with the already reported functional PcR-based marker for Xa21(p TA248), we designed a single-tube multiplex PcR based assay for simultaneous detection of all the three major resistance genes and demonstrated the utility of the multiplex marker system in a segregating population.

关键词： rice bacterial blight resistance xa5 xa13 Xa21 functional marker multiplex PcR

Inhibition of quorum sensing in chromobacterium violaceum by Syzygium cumini *** Pimenta dioica L.

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Asian Pacific Journal of Tropical Biomedicine 2013年第12期3卷 954-959页

作者： Halkare Suryanarayana Vasavi Ananthapadmanabha Bhagwath Arun Punchapady Devasya rekha Yenepoya Research center Yenepoya UniversityUniversity Road

Objective:To investigated into the anti-quorum sensing(QS)activity of Syzygium cumini L.(***)and Pimenta dioica L.(***)using chromobacterium violaceum(***)***:In this study,anti-QS activity of ethanol extract of Syzygium cumini *** Pimenta dioica *** screened using *** cV026 biosensor *** bioassay guided fractionation of *** and ***,ethyl acetate fraction(EAF)with strong anti-QS activity was *** of QS regulated violacein production in *** ATcc12472 by EAF was assessed at different *** effect of EAF on the synthesis of autoinducer like N-acyl homoserine lactone(AHL)was studied in *** ATcc31532 using its mutant *** cV026 by standard ***:EAF inhibited violacein production in *** ATcc12472 in a concentration dependent manner without significant reduction in bacterial *** inhibition of violacein production was evidenced in 0.75-1.0 mg/mL concentration of EAF without inhibiting the synthesis of the *** biosensor overlay profile of EAF revealed two translucent spots in *** and *** that inhibited c_6-AHL mediated violacein production in *** ***:This study indicates the anti-QS activity of the tested medicinal plants against ***.

关键词： Anti-quorum sensing chromobacterium Medicinal plants Quorum sensing Pathogenicity

Synthesis and photoluminescent performance of novel europium(Ⅲ) carboxylates with heterocyclic ancillary ligands

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Rare Metals 2022年第4期41卷 1342-1352页

作者： Priyanka Dhankhar rekha Devi Sushma Devi Sangeeta chahar Mandeep Dalal V.B.Taxak S.P.Khatkar Priti Boora Department of chemistry Maharshi Dayanand UniversityRohtak 124001India

Five novel europium(Ⅲ)complexes with 2-[4-(dibutylamino)-2-hydroxybenzoyl]benzoic acid(DAHB)as primary ligand and bathophenanthroline(batho),2,2’-bipyridyl(bipy),5,6-dimethyl-1,10-phenanthroline(dmph),1,10-phenanthroline(phen)as ancillary ligands were syn-thesized via solution precipitation *** structural formulae of synthesized complexes were speculated to be Eu(DABH)_(3)·2H_(2)O(c1),Eu(DABH)_(3)·batho(c2),Eu(DABH)_(3)·bipy(c3),Eu(DABH)_(3)·dmph(c4)and Eu(DABH)_(3)·phen(c5)by elemental analysis,infrared spectroscopy and proton nuclear magnetic resonance spec-troscopy(^(1)H-NMR).The photoluminescent properties and thermal stability of the complexes were investigated by photoluminescent spectroscopy and thermogravimetric analysis(TG-DTG),*** commission Inter-nationale de I’Eclairage(cIE)color coordinates,Judd–Ofelt intensity parameter(Ω_(2)),total quantum yield,intrinsic quantum efficiency and energy transfer dynamics of com-plexes were also *** excitation spectra of com-plexes are extended up to visible *** complexes exhibit characteristic photoemission of Eu^(3+)metal ion with high color purity in red region attributed to efficient energy transfer from ligand to metal *** replacement of water molecules from coordination sphere of europium ion by ancillary ligands results in enhancement of luminescent properties of the c2–c5 complexes,indicating that ancillary ligands act as additional light harvesting centers in sensiti-zation *** thermal studies show that these complexes are suitable for meeting the requirement of temperature for fabrication of OLEDs devices.

关键词： Photoluminescence Europium Sensitization Aromatic carboxylic acid Energy transfer dynamics